Nobody is forbidding behavior they deem inappropriate, they're refusing to finance behavior they deem inappropriate, big difference. And by "deem inappropriate" we don't just mean "dislike it", we mean "not within the scope of the stated reason you requested this money in the first place." "You can't buy lottery tickets with food stamps" is not the same as "you're not allowed to play lottery if you're on food stamps" and it's not the same as disallowing e.g sex out of wedlock while on food stamps.