Plenty of atheists go to church. There is no good reason not to. Certain previously Christian denominations like the Unitarian-Universalists or the Hicksite Quakers include both whole congregations composed mostly of atheists and others that are largely Christian. It may speak to their childhood and make them feel supported in raising their own children. It may be uplifting morally to hear from other morally-minded people, even if the source of their judgments is alien to you. It may simply be a beautiful experience. And there is no prohibition accepted by any atheist I have encountered upon accepting cultural values, whatever their original basis, as long as they make sense. Daniel Dennett has admitted he sort of likes church.
There is nothing particularly 'un-atheist' about habits of altruism, the appreciation of ritual, or adherence to Western cultural norms. These things are not Christian, just human, unless you try to make excuses for them by creating fanatical logic out of whole cloth.
The question of what would constitute hypocrisy toward atheism depends upon the reason the person or their community decided against theism to begin with. The easiest positions to find hypocrisies against are moral ones. So I am sticking here with moral arguments that any decent God who would make contact with humans should have prevented, rather than favored, the behavior of Christian institutions. (And any other kind of superior being might exist, but should definitely be called by a different name than the one any religions ever use -- to call such a thing God would be to devalue, misrepresent or unfairly impune it.)
One lot of atheists see religions as reasons for needless divisions. Religions, as suggested by the etymology of the term, 'to link back', tie one to traditions. Sometimes those traditions are barbaric, and they are supported by convenient supernatural logic. (If I were straight, I am sure I would be an agnostic. But I am not, so I am an atheist.) The nature of supernatural beliefs means there is no way to compare them or compromise around them that gets to the core of the issue. Any test of them would generally be 'natural', or worse yet 'worldly', and they could be expected to escape disproof.
At the extremes, we have seen tons of blood spent in wars where the real causes are inconvenient to express or admit, and the real reasons men went were entirely about tribalism and tradition, but the official cause was some point of supernatural faith. Rejecting a faith because it keeps you barbaric or barbarically paints you as evil, and then feeding back into the same nonsense, is hypocrisy. So I would say that trading theism for some other cover story to excuse your conflicts (say capitalism, nationalism, or socialism) is 'practically Christian'.
Other forms of atheism are, in origin, 'freethinking'. The reason to reject Christianity rather than just ignoring it has to do with how Christianity responded to attempts leave, in days gone by. For such a person to then cling to any other form of thought-dictating authoritarianism is hypocritical (even, in my opinion, the attempt to remake the society in an atheist mold.) To go around trying to create a different kind of hegemony on thought is 'practically Christian'.
There are approaches to atheism that see how religions are bad for the soul. The notion of 'slave morality' or of the need for authority that makes one afraid to surpass your parents, so much so that you go out of your way to create a super-overparent that you can never conceivably surpass. This kind of atheism could possibly see altruism of the wrong types as hypocritical, and an unthinking charity as 'practically Christian'. (This kind of behavior is really bad in the long run. For instance, it keeps undeveloped countries poor by preventing the rise of any effective, local middle class.)
There are approaches to atheism that simply consider religion a serious waste of time and resources, to the degree it is a threat to our culture. But this lays a burden upon them to do better, and not to fritter away their energies on any other abstract, subjective and pointless pursuit. For such an atheist, the most 'practically Christian' career would be to retire into preaching atheism (perhaps from, say, biology.)