Living in Mexico on a tourist Visa. Legal or Illegal?

We just spent 4 months this year living in Mexico in a lovely little town called Puerto Morelos , 30 minutes from Cancun. I met many and many people living there on a tourist visa and going out of the country once in a six months and going back the same day. People just got used to this lifestyle now. Good for us that more and more countries start to approve visa applications online https://evisa.express/. Only few years ago i spent hours and hours in a different embassies and collecting millions of different docs.