I have never seen a plastic bottle that bears an expiration or beyond use date for the bottle specifically, and would be fascinated if you could share some examples.
From a theoretical standpoint, yes, there could be concerns about plastic degradation and leaching over time, especially in unstable or harsh environments where exposure to things like UV radiation etc. could be problematic. However, not only has Pfizer/Hospira specifically engineered the plastic in their MDV's to be extremely robust, but recent Jano tests of Hospira BAC that expired over 10 years ago (I'm actually thinking it might have been more like 15 years ago) showed perfectly intact BAC water with zero contaminants so ultimately - at least in regard to Hospira BAC - the theory is a non-issue.