You could of course be completely correct. I'm baffled though how they intend to filter applicants, interview them, and decide how to accept all in a space of less than a month for thousands of applicants? I would imagine it isn't possible unless you're brutally filtering everyone.
No disrespect to anyone but applying to one group does not increase your chances. Plenty of alum have applied to multiple groups. In the end it's about fit. I applied to one because it was my best fit. If you think you had a good fit for 3 — relax you'll be fine. Trust your gut.