Here's a new term i've invented. Feel free to post your own.
markeshar - adjective used to define any service which has no non-trivial advantages over its competitors but is simply dominant because it has a big market share advantage. May also be used as a noun to refer to any such service.
example:
"their website sucks in every way but it's a markeshar site, so there is no point trying to compete with them"
