foul play on my mobil 1 synth oil change at dealership ?

Well I brought my car in for 10,000 mile service (oil change and tire rotation). I gave them mobil 1 synth and specifically requested 3.5 quarts be put in and that I wanted the .5 remaining quarts given back to me. I was pleased after the service that .5 quarts were returned to me and figured they followed my instructions. My wife drove the car 100 miles and tonight I checked on a few things. First off, I checked the tire pressure in all four tires. It was obvious that the tech rotated the tires without readjusting the tire pressures. Prior to rotation i set the rear tires lower than the front. This setup is the norm on all priuses although some owners may choose to use higher numbers than the placard on the door jamb. Even doing so... the rears are always softer relative to the front. The two rear tires weren't even the same psi - both different. I'm not sure what pattern rotation should be done. One or both of the rear tires were at pressures higher than front and the front's were lower than the rear. 'Nice attention to detail' (NOT) from the dealership mechanic right ? Well at least they did the rotation service... not sure if the rotation order was right or not howerver..

The oil levels looked correct. Slightly below max mark as should be with 3.5 quarts. Admittedly, the oil was circulating for 100 miles since changed but it looked a bit more yellow than the mobil 1 synth i had from the .5 quarts they gave me back. Also, I had another batch of mobil 1 remaining from previous change done at a different dealership. It didn't quite match in color that batch either. I felt the oils letting a few drops slide between my fingers (don't get too excited... its only oil guys - LOL). Anyway, the oil from the car's dipstick felt quite a bit stickier than the fresh oil from the quart bottle. The fresh synth definitely had much less friction than the stuff from the car with 100 miles on it.

My question is this... should the oil from the car at 100 miles look slightly more yellow and feel differently. Would the mix of the undrained old oil and the new oil from the oil change cause this to look and feel differently or did the same mechanic that screwed up my tire pressures keep my mobil 1 synth for himself and put the usual dino oil the dealer always uses into my car ? Damn I hate not knowing... Next time I'm changing it myself and self documenting the change. Just had THEM do so it would be documented for warranty purposes.

 

Thanks for the information on the characteristics change of the Mobil 1 after having run the car for a while. You also mentioned that prior to changing it you had a blended oil. Prior to my change I had Mobil 1 (assuming change done prior to the one this week at a different dealership was legitimate). Sorry for sounding paranoid. When I sit back and think about it rationally, the difference in Mobil 1 and Dino oil is maybe 3-4 dollars a quart. Were talking about a total of 4 quarts. Mechanics get paid decent money. Why would they screw around for such a petty bounty. I think they could afford to buy their own mobil 1 synth for their cars and not risk looking shady while on the job. They have to figure that the customer giving them their chosen oil is already highly particular and more likely to uncover something devious than the typical customer who unquestionably pays for all the services the dealer says NEEDS to be done.