According to the EPA, the difference in fuel economy isn't that big:
https://www.fueleconomy.gov/feg/bymodel/2016_Mazda_CX-5.shtml
https://www.fueleconomy.gov/feg/bymodel/2017_Honda_CR-V.shtml
CX-5 FWD 2.5L = 26 city, 33 hwy, 29 combined
CR-V FWD 1.5L = 28 city, 34 hwy, 30 combined
I also looked at the real world data from Fuelly:
http://www.fuelly.com/car/mazda/cx-5?engineconfig_id=53&bodytype_id=&submodel_id=
http://www.fuelly.com/car/honda/cr-v?engineconfig_id=37&bodytype_id=&submodel_id=
Average for the CX-5 2.5L since 2014 looks to be a hair over 26.
Average for the CR-V 1.5L is 27.5
One important thing to note is that the Fuelly data includes FWD and AWD models, I'm guessing mostly AWD. The difference between the FWD and AWD is 3 MPG combined in the CX-5, but only 1 MPG in the CR-V. So if you could compare data from only the FWD models, I'll bet the numbers would be pretty much the same, well within the margin of error considering the 1.5L turbo is a new engine and there's not a lot of real world data yet.
FWD CX-5 is 31 and 24. Which is more realistic - added 90 lbs hurt city mpg. 31 for a lower profile on highway is more accurate when my 16.5 never sees even 30 itself.
I might be able to hit 33 in 16.5 hypermiling within reason and being under 70 mph on a non windy day here in Texas with only me as an occupant and A/C turned to low, display turned off and music volume around 6 - praying to the mpg gods.