Depending on where you live, your experience with this will vary. I cannot think of a single state in which I've lived where it was legally permissible to buy beer on Sunday morning. Why? Jesus, of course! The real question is why the rest of us go along with this nonsense. Aren't those of us in the U.S. always hearing about how we live in a "free country?" Why do we allow Christians to restrict our freedom like this? When was the last time any of us contacted our elected officials and demanded that they change these antiquated laws?
I suspect that part of the answer is that we are so used to hearing about how we are supposed to "pick our battles," and this probably does not seem like more than a minor inconvenience. But it is an inconvenience. I do my grocery shopping on Sunday mornings because that is the least crowded time when I'm available to do it. And back when I used to drink, it was a pain in the ass not to be able to buy it when I was there anyway. I'd have to remember to make another trip on another day, burning more gas and putting unnecessary miles on the car. I could buy everything else I needed to enjoy the football game on Sunday morning except for the beer.
Although it no longer impacts me personally, I still find the idea of Christians restricting our freedom unnecessarily to be a troubling one. Christians should have the absolute right to refrain from buying beer; they should have no right to impose their warped morality on anyone else. Our elected officials are not supposed to be able to push Christianity by legislatively imposing Christian morality on the rest of us. Most people can easily wrap their heads around why it is a problem for Muslims to prohibit non-Muslims from drawing Muhammad. Why is it so damn hard to understand why it is a problem for Christians to prohibit non-Christians from buying beer on Sunday mornings?
Stop your whining about "false equivalence!" I'm not saying the two situations are the same. I'd be arrested for obtaining beer on a Sunday morning (of course, I could be arrested simply for drinking a beer in the privacy of my own home too); I might be murdered for drawing Muhammad. I acknowledge the difference. But do you see the similarity? Do you see that in both cases we have adherents of a religion finding it insufficient to practice their religion? Instead, they must impose it on those of us who find it ridiculous. I don't get why so many of us go along with this.
Religious believers are fond of asking atheists why we occupy ourselves with matters of religion at all. This is the sort of thing that leads us to do so. Far too many adherents of various religions are not only unwilling to keep their beliefs to themselves but seek to impose their beliefs on those of us who do not share them. Being unable to buy beer on Sunday morning may seem trivial, but it is a symptom of a problem that should not be ignored.