Odd Jessie Package Programs Shown in Gnome?

["Thomas H. George" <lists@tomgeorge.info>]

The gnome activities show all applications produces three pages of
program icons many of which are gray gear wheel icons.  I clicked on a
few which did nothing. Trying apt-cache show on some of these icons'
names I determined they related to screen savers. 

Can I get rid of them?

I realize that selecting show frequent applications displays only icons
of programs I have used. But frequent implies transient. As I use more
and more programs some may be used infrequently. Will rarely used
programs disappear from the list of frequent applications?

A minor quibble. So far Jessie is very nice.