You answered your own question by citing the reason.
So, it’s acceptable if the owners of the polling place restrict your behavior for five minutes for reasons that are not religious? If, for example, they have a general rule of not having food or beverage in the facility for whatever reason - safety concerns; the carpets are new, they don’t want them sullied; they’re concerned that dropped morsels and drops will attract vermin; whatever - that’s okay, as long as those reasons aren’t religious?
Now you’re reaching into the minds and hearts of those whose facilities it is and telling them that they may only require restrictions for strictly secular reasons. Thus, you don’t really have a problem with the “no coffee” rule. You have a problem with its religious motivation.
I think that makes you a religious bigot.
Good luck with that.
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