Now a days all these places are called as travel centres not just truck stops. So thats why i guess any one who is travelling can use the facilities. If you fill minimum 50 gallons of fuel or you pay the money for shower. This is how ot works. As Mr. Sean said it costs 12 to 14 dollars for a shower otherwise.
Technically, the showers are for professional drivers. However, they don't ask to see a CDL, so anyone can use the showers. Typically, showers cost $12-14 per person.
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