Garmin 66i / elevation gain question

I'm a longtime Garmin handheld user having owned one of the original eTrex models then upgrading to the Colorado series onto the 64st.  I have now sold the 64st and got my new 66i yesterday.  I did a search and didn't see anything this specific.  

I created a route around my neighborhood via the GAIA GPS website.  I saved it as a .gpx file.  I transferred the file to the 66i.  I brought up the route in the route planner on the 66i and pressed GO.  I started recording.  I was able to follow the route I created fairly easily and saved it when I returned home.  I only did a short half-mile walk around our neighborhood.  There was a very short elevation gain of approx. 60 feet.  I sync my cycling and hiking activities to Strava.  I'm assuming a few of you avid hikers use Strava or a similar activity tracking app.  For some reason, Strava didn't acknowledge the 60-feet of gain indicated on my 66i.  Didn't seem to have any issues recording the rest of the data, but for some reason - it omitted the elevation gain.  Not a big deal for this initial test, but during longer day hikes with a couple thousand feet of elevation gain - I'm hoping this is factored into my recording.

Thoughts?  Is it simply due to the minimal gain?  Is it something happening (or not happening) between the GPX file and Strava?