I think if you put html sitemap on footer so this is not a spam link. Its good if you do this , also help in SEO if you add on footer.
You can add sitemap in footer and this is not spam. It helps in SERP rank better.
adding on footer may not be beneficial because sometimes it is very difficult for search engines.
I will suggest you to add that in header as it is loded fast and search engines first crawl the header and then the other parts of the website...
In-fact by doing that you would make it easy for the user to find the page on your site more easily.
I already have all category & sub category links on my all pages as header. do you think i should add all those link to footer as HTML sitemap which will have all those link. it might be consider as link spam.
