AW getting gas at Maple and Inwood is definitely a head-scratcher. Why? As others have pointed out, a more direct (and safer?) route from the gym to AW's house would've been to go west on Lemmon, then north on Inwood.
This is my biggest question too. However, maybe he took the "highway" route home? I asked some of my former Dallas neighbors what route they would take considering the time of day and one immediately said they would take the highways - 75 to the tollway or I35. Travel time at that time of day is within 1 minute of the more direct route thru town (via Lemmon). Maybe he wanted to open up the Porsche on the highway when there was no traffic??
Was the location of that RaceTrac gas station near (or closer to) AW's Porsche dealership? Maybe his last minute plan that morning was to top off the loaner, run it by the dealership, drop it off, and pick up his own vehicle.
It is on the way to the Porsche dealer. However, their service do not open until 8a. And, it's only 1/2 mi from his house, so why make special arrangements to pick up before hours?
Which, now that I think of it... Wouldn't a Porsche dealership's after-hours drop off/pick up location be a prime spot where thieves might think they could easily ambush a customer picking up a nice car? (though you'd think a dealership would have lots of CCTV, and maybe even a security guard at such a location after hours..).
Or was the RaceTrac gas station perhaps on the way to one of AW and his husband's house renovation projects? If so, maybe he was planning to run by the house project real quick to check and see if something had been done. Just guessing, but he probably had 30-45 min before needing to head back to the house for a 7:30 am call.
This is interesting. Maybe he was going to drive by a place he and Rusty had an eye on and was caught in the wrong place at the wrong time.
All just speculation
Eta typos, grammar