What happens as a result of Curley's foolishness in Chapter 3 in Of Mice and Men?
Throughout the story we see Curley as obsessively jealous and insecure. To be sure, he has reason to fear given his wife's alluring behavior around the other men. However, his efforts to keep her to himself actually contribute to his wife's loneliness and lead ultimately to her death.
Lennie's experience in Weed is similar in that by clinging too hard to what he wanted he ultimately lost the security he wanted. Lennie loves to touch nice, soft things. Mostly these are puppies, rabbits and mice. They calm him and give him happiness. In Weed he wanted to touch a pretty red dress. Unfortunately, a girl was wearing it at the time. When she screamed, he was frightened and confused and clung all the harder. As a result, he and George had to run away -- mostly likely leaving some earnings uncollected and certainly having to start all over again towards their dream.
A quote from the book captures the parallel between these two situations:
. . . he holds on 'cause that's the only thing he can think to do.