Why is price discrimination acceptable in pricing?

Price discrimination is used to charge different customers different prices for the same product or service for legitimate reasons. It is not illegal unless the competition is affected. For example, roses and other flowers are very expensive around holidays such as Valentine's Day and Mother's Day because the demand is so high and flowers are a popular gift for these holidays. Restaurants offer early bird specials or other promotions (cheaper drinks or appetizers)before 6:00 pm to encourage customers to come before the restaurant starts to get busy and to "even out" the business.