3,000 rounds is like $140. In 22's. Give or take, depending upon brand. I don't buy bullets for reloading in bulk, so they cost around 10 cents each. Again, a few thousand of those isn't a grand either.
For myself, I like keeping a few thousand on hand. For each caliber I have. Not enough to trip over, but enough that, if the round isn't available for 6-12 months, I'll be fine. After that, well, has anything been that unavailable for that long?
Doesn't hurt to stock up when you can. Remind me how often ammunition prices decline. If the price meets criteria, buy some, save it for a range day. But, you do have to take into account storage of said ammunition, both in terms of where to put it and how to keep it from going bad. I don't think it has to be kept in a humidor but it's unlikely you're going to store 10k under the bed either. At some point you have to ask your self if it's really the investment you want (a few thousand in ammunition vs money towards loans / whatever).
I must say, I was reading in a different thread (elsewhere) about someone complaining that hoarders were "ruining" for everyone else. Newbie shooters couldn't find ammo, those who don't buy into the scare can't buy ammo... No one can. And there's no ammunition ban coming. I still think it's free economics, but I think I agree to the point that, it's best to stock up before not during a "crisis". Same is true of gasoline for the generator, having a generator on hand, toilet paper, bottled water, you name it.