"富人比穷人消费频繁" 英语是 The rich have more frequent consumption than the poor.
消费的的英语是 consume (consumption 名词)
spend 的意思是“花钱”
不过“消费频繁”不是英语习惯说法,建议这样说：
The rich consume more than the poor
或
The rich spend more than the poor