Each shareholder can attend the Annual General Meeting (and any other meeting such as an EGM), which can have lavish catering. Historically, the bulk of the attendees of AGMs are retirees, and attending an AGM is something to do, potentially with a free feed.
They post you an annual report, which is exciting if you don't get much mail or reading material.
Why one person would own 30 lots of one share... thirty copies of the report? For his lending library? More likely, though, is that person can provide a rent-a-crowd of activists to attend an AGM and disrupt it. Shareholders can appoint a proxy to attend a meeting and act on their behalf. If the action was asking awkward questions of the board, for example about cutting staffing levels (unions have been known to do this with their single-share holding members), it could tie up the AGM and cause angst.