@Oatmeal
Hiya! I just checked with Squid and its fine because you have to pay for each individual card, we get nice presents and if we didn't want them, we can always disable receiving cards from non-friends. So feel free to send away!
If you're still concerned, maybe consider sending out a few every day of Snowmelt instead of all at once. But either way, you are good to send out as many as you like!