Should religious leaders....?

[spotted and speckled]

My sister lives in an area where there is a shortage of good churches, but no shortage of places that call their buildings churches. After a 2 year search, she found one that she likes. Pastor is great, biblical, personable, etc. He has put someone in the pulpit several times recently that has a very humanistic view of scripture (as opposed to a God-centered viewpoint), which disturbs her. The regular pastor does not have this human-oriented theological viewpoint.

I'm in a different city, so I have missed the fill-ins sermons. But the pastor has started posting stuff on Facebook & twitter about some product he has been using to help him lose weight, feel better, etc. He's not selling it, but I think his wife is. I don't think my sister has seen this and I haven't discussed it with her. This disturbs me, maybe because I have previously seen church turn into a business for some leaders.

Should a religious leader use his/her platform to advance a product, or a political agenda, or anything else? (Edit--anything not related to doctrine or education of doctrine)

Thoughts? Opinions?