I just checked. I live 4.5 miles from Wilson, closer even than McCarthy.
We don't get together, we don't shop at the same stores.
Your premises that NW DC and Bethesda "are the same place" and that living 5 miles away from someone else in DC Metro proves anything whatsoever, are both completely idiotic.
The cold, hard facts of life in Montgomery county are that planning and zoning are done with such a heavy hand that if you shop in one of the "corridor" areas, you will do so in a limited number of places, and you will also have traveled up to 10 miles to get there!
I bet you never noticed that.
Having lived in the WashDC metro area since 1966 I'm pretty familiar with all the major neighborhoods, as well as Montgomery County's "wedges and corridors". I have friends and associates from Gaithersburg to General Smallwood Park, and from Port Tobacco to Harper's Ferry.
There's probably not a major road I haven't traveled.
If you check out this page:
you can see Bethesda's SKYLINE right on the DC line.