Complaint Review: Tuffy Tire and Auto; Land O' Lakes FL

I receently moved from North Carolina to Land O'Lakes, Florida

Today I visited the Tuffy tiire and auto repair shop for an oil change.  Once the service was completed, the desk kclerk advised me that the fluids shoud be flushed and replaced in the transmission , power steeering, and aijr conditioning. Since the vehicle had 58,000 miies with only regular oil changes I agreed. 

 Once the work was completed, I was presented with the bill whichi included "shop suppliess in the amount of $28.80.  Thhis was defined on the bill as follows: "This charge represents costs and profits to the motor vehicle repairr faciility for miscellaneous shop supplies or wasts disposal. 

I've never seen a charge for "shop supplies" on any other automotive repair bill before.   At no time before the hwork was done was this charge pointed out to me.  When I asked about it I was told the cost represesntly 10% of the bill, not to  exceed $30..

This was new to me.  Do all, or most, auto repair shops make such charge$?  If not, I belieie I should receive a refund of the $28." 

George D