I took my 2010 Civic to the mechanic. He indicated that the tire pressure is low, and suggested rotating my tires as a fix.

I thought tire pressure is already pre-specified and should be at a specific value (eg. 32PSI, which is what's indicated inside the front door). Assuming they do re-pump it to the target pressure:

• Is there anything specific about low tire pressure that necessitates rotating it?
• Since Civics have a low-tire-pressure indicator, is this something that can only be done at a mechanic?

NB: this mechanic is known for recommending changes that may not be necessary, and pressuring buyers into saying "yes."