The days of chicken buses and hitch hiking are gone along the coast, though you will still see hitch hikers on the beach road in Tulum getting rides into town. Hello fancy air conditioned vans and big massive buses with television, movies, and in some cases on bus beverage service. Public transportation rocks for those quick trips, or even not so quick trips making the entire Yucatan easy to get around and open for all to see. We currently are a one car family and if I am going to Merida or Tulum or Playa for a visit I am loving the collectivo service up and down the 307 hwy and really loving the executivo primero class-o bus that goes to Merida!
Collectivos are 12 passenger vans that you can flag down on the highway between Cancun and Tulum. Most expensive trip, 35 pesos or 3 USD. Buses are to picked up at any local bus terminal and travel all over Mexico. Merida takes 4 hours and you can read, watch the movie or if you decided pay a few pesos more have food and drink service , for a free, on board. That rocks!
Check out the maps of the Riviera Maya and decide which public transportation will take you where. The greatest good of all is knowing that by sharing you are being a responsible traveler that is taking care of the environment.