[[WMG: There really was only "lots of sugar" in Eddie's brownies.]]
It could be that Mark is so weird on his own that he doesn't even need drugs to see himself in a Gwar video.
[[WMG: Lucas has a anti-social disorder]]
[[WMG: Lucas believes the store has magical powers]]
Several remarks he makes seem to imply that Lucas believes that the store is in some way magical, and benevolently so at that. Notably, his claim to be "guided by a force much greater than luck", and his assertion that nothing bad would happen to Debra now that she was "in the store."