Changing habits?

Why does it seem (to me) so hard for some people to change their habits?
I saw a flyer today:
"5 free workshops to help parents and guardians find the balance for promoting healthy nutrition and physical activity for the whole family. You care about your child's health and well-being. You can take steps to help your child make smart nutrition choices, increase physical activity, and reduce their time spent watching TV or in front of the computer."
----I agree with all this.

"Call today to sign up for free workshops.
Get ready to have fun and learn!
Attend 5 workshops.
Learn new tips and develop skills to promote smart food choices.
Receive great recipes the whole family will enjoy.
Meet other parents and guardians and get support from each other.
Win prizes.
Earn a certificate and 3 month membership."

----OK...is this REALLY enough to change day to day habits? From my experience, I'm skeptical. I would like to know about the follow up study of how many families maintained the "healthy habits" one year down the road.
It still seems to me that motivation is a big factor...in my world, the information is out there. All I have to do is go find it, implement it into my life, and there's the change..gee that seems easy..but I know it may not be that easy for everybody:)