Thanks! Yes, they do have a hole into which a grease zerk could be threaded if you drilled & tapped. But...my experience has been a lubricant like Lubriplate will last nearly forever and the bonus is in hot weather Lubriplate won't spread and make the hinge area look like you just fried hamburgers on it. Here is a link:
https://tinyurl.com/4we5z2cx This is good up to about 175 degrees F and then after 180 F you'll be flirting with the drop point. Some of the new high temp wheel bearing greases would be ok to use on these, I think. Or mix Lubriplate with powdered graphite and that should be slippery for a long time. The problem with squirting oil in that hole is it doesn't migrate to the top of the hinge pin but it does drop down into your body.
