On the Chevron category it didn't take "begin with oil companies" - that ought to be acceptable don't you think?

I did think about that, but the problem is that 'technically' such an answer would be incorrect.

'Shell' itself is not an oil company; the official name of the oil operation is 'Royal Dutch Shell', and 'Mobil' is part of 'ExxonMobil', which actually owns 'Esso'.

That leaves 'Chevron' which is the only answer in that group which is, in and of itself, an oil company; however all four are names of gas/petrol stations.

I hope that helps, and by all means, have the point since you clearly had the idea.

the dynasties one was so hard!

Rumour has it im still looking for the fourth Alabama town