It's not spam. These communities don't just magically spring up from nothingness, there are people that have to contribute to these to get them started and to get them to grow. If you don't like what you see, then block them, but go take a look at @Martineski@lemmy.fmhy.ml profile and you'll see they've done more to help this instance and multiple communities grow than just about anyone else.

Lemmy is still new, if you have a suggestion on how you would like to see things improved good, but complaining about something that you aren't thinking about thoroughly isn't helpful at all.