I'll absolutely agree that bugs that only show up on particular device/OS/network/etc combinations are harder to detect, diagnose and fix. But when those bugs are generally applicable (and the particular combination is just surfacing the underlying issue) I'd say it is better to be thankful they came up instead of frustrated by fragmentation.
After all, when it is a general bug that just happens to be masked most of the time, it is a buried bomb just waiting to explode when the surrounding context changes. In my opinion, detecting and defusing more of these issues sooner rather than later is a good thing.
Personally, I'm reminded me of the issues I run into when writing cross-platform code (or code that needs to work with multiple versions of tools and libraries). The upfront effort to multiple environments (or the effort required to add the new environment) is usually significant, but I'd say the improvement in code/software quality is an often unrecognized benefit (over and above the reason you're supporting the new environment in the fist place).
