Jewel !
Yes it's true. In town Krk on the same Island Krk, there are beach just for pats. I have never been there, but I read it in local newspapers. Also on the Island Krk, there is town Baska with long sandy beach within a camp. It's a blue flag beach, a there are part of beach where pats are allowed.
How do you get there?
If you are traveling from Italy and entering Croatia on border cross RUPA or PASJAK.
When you enter croatia follow the signs for town "Rijeka", it's biggest city nearby and 3rd in population for croatia. So the signs will be there..When you reach Rijeka, do not enter the city follow up for Split and Kraljevica and Otok Krk.
About 25km from city Rijeka in direction of city Split, there will be town Kraljevica. Near it is a bridge for Island Krk.
Sign should be OTOK KRK means Island Krk and MOST KRK means Bridge Krk.
It's very important that you turn about 25-28km from road for Split, to town Kraljevica and "Most Krk"
If after 35 km there no signs for Kraljevica or Krk then you already miss it.

but it's hard to miss it.