I have read post in the past that explained that the epoxy that Hobbico and others use in assembly of their ARFs and RTFs cure to a creamy white color and looks like hot glue but is really epoxy.
I have seen this in some of my ARFs and although it looks like hot glue it is not.
I can't say this is always the case but so far all the Hobbico ARFs I have dealt with have been well built and caused no problems at all.
Some of the older ones are covered with contact paper that can be somewhat difficult to repair but still airworthy to be sure.