Alignment service near Monroe, LA

This afternoon my wife dropped my vehicle off at the Firestone location at the Pecan Land Mall in Monroe, LA. When I arrived to pick my vehicle up I saw that I had been charged $29.50 to replace a burnt bulb on the rear driver side light. This seemed odd to me because the bulb only cost $2.50 and takes less than 5min to replace. When I asked the person at the register about this he told me with a strait face that the remaining $27 was for 3/10 of labor costs which I assume is an hourly calculation. If my assumption is solid then this means the ace mechanics at this location who charge $90 an hour took ~20 min to replace a light bulb... on what planet does this make sense? It may take my wife ~20min to change a light bulb on a vehicle, but she is not out there charging $90 per hour. I'm not sure what this message will accomplish, but I hate that these people who represent the Firestone brand are perpetuating the negative perception of mechanics by using shady business practices. These guys only screwed me out of $18 dollars, but I see no reason why they wouldn't try to pull one over on someone who needs more expensive services. Hopefully this post will save you from being that victim.