When I'm going through a real OCD period or right after one I'm the same way, church, planes, restaurants, i really feel more comfortable with an aisle seat. For whatever reason it gives me that sense of freedom to escape if I need to, even if I don't really need it. For me its not the dirt thing, just that, but it was especially strong when i first started having OCD as my fear was throwing up and I wanted a way out (of course my fear never came true, stupid OCD

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