Most relevant in modern global economies: lack of available alternatives. One of the primary reasons for combination in low-margin markets is to gain pricing p

Most relevant in modern global economies: lack of available alternatives. One of the primary reasons for combination in low-margin markets is to gain pricing power. And even if there are 2-5 entities in a given market, informal price collusion is far from unheard of. If OP wants an intro to the determinants of price elasticity, starting here would be a good idea: https://en.m.wikipedia.org/wiki/Price_elasticity_of_demand https://en.m.wikipedia.org/wiki/Price_elasticity_of_demand