Jonathan, I'm not sure about the foot but it sounds like it's just from wear and tear. I have had a few of my cigars in the humi actually flare at the foot a little and split but this is the first bug problem I have ever had or seen personally. Thankfully it was in a bag of sticks that were in a large ziploc bag already.
Now the weird part, I have a wine-o-dor and it usually sits at 65/65 give or take a little. I thought having a wine-o-dor and isolating cigars in ziploc bags when they first come home would help to not have the problem I just had. I have noticed the humi going over the 65* mark lately almost to 72* before cycling on to cool back down to 65*. I don't know how much of a factor that has been but I am chalking it up to bringing home a bad stick. Last night after I saw that I tore the whole thing down and looked at all the sticks in there and yea, like you it took hours. Now all of my cigars are in the deep freezer, I am cleaning out the wine-o-dor and hoping that doing this will get rid of any others that might just be in there somewhere.
I can tell you after this all cigars that come home go into the freezer now before going into the humi.