Yes.
The surface of plastic can attract microbes due to many issues, including chemical interaction between plastics and other products, oil contamination from fingertips brushing against them, or other handling that introduces oils. The build up of micro-organisms will happen more quickly on surfaces that are wet or moist. When these micro-organisms or their products accumulate on one place for a long period of time it creates the right environment for the insects to breed. Roaches are attracted to stagnant water so if your water bottles have been sitting out in the sun all day they are much more likely be breeding ground!