How do I say "they discount so much I can't help but buy" using 打折? Also how do you say "unlike" in Mandarin? I want to say a sentence such as:

They discount so much I can't help but buy!

I went as far as 这家商店打折那么多， but need help with finding a Chinese expression that has the same impression as &quot;can't help but...&quot; in English.
Also, how do you say unlike in Mandarin?

Unlike the Chinese, the British add sugar to their tea.
不像中国人， 英国人把糖放进茶里 （or 英国人在茶里加糖）

I came up with the above sentence and added some variety for the sake of it. Would also like some help on this.
"They discount so much I can't help but buy!"


Direct translation : “他们打了那么多折，我不买不行呀！”

But for the part "I can't help but buy!" can translate into many option, i just pick out one that i think is the suitable ones.

small info : the discount compare to china is a different phrase. If is 25% discount in mandarin we would say 七五折, which is 75% of the original price.

For Unlike, 不像 i think is acceptable.