Need advice on signing a new employee agreement for my current employer of 8 years?

After 8 years of employment, my current employer is asking me to sign an "employee agreement" that contains non-compete clauses and several other items. I'm sure if I don't sign I will be shown the door, as that's just how they operate. Here are a few things that bother me and I wonder about the legality or if they would stand up in a Missouri court.

1) Exclusive Business. Employee agrees to be employed by Company and to perform faithfully the duties assigned by Company. Employee shall devote all working time, attention, knowledge, and skills solely to the Company. The Employee shall not work or engage in any other business or work activities unless Company has first approved in writing such other work or business in each case.

Can they require that I notify them of any other job or business I may have outside of their employment and let me go if I don't? I'm an hourly employee and my thought is that whatever I do outside of their business hours is none of their concern as long as it does not compete with their business.

2) Reimbursement for Training Costs. Employment with Company is on an at-will basis and remains unchanged throughout period of employment, including Employee's Training. If Employee voluntarily terminates employment with Company within twelve (12) months after attending training classes ("Training"), either in the offices of Company or at another location, Employee shall pay to Company a sum equal to the actual out of pocket expenses incurred and paid by Company for the Employee’s Training ("Training Cost") as reduced by one-twelfth (1/12) of the Training Cost of every complete calendar month between the date of the Training and the date of the Employee’s employment termination.

Can this be enforced? Am I not able to pursue my livelyhood and find employment elsewhere without the threat of paying them back for training hanging over my head. As long as I am not going to a competitor of their's where I would use this training and am changing industries, how could they enforce this?

These are just a few of the things in the agreement that bother me. I understand about the ones concerning keeping intelectual property and customer lists private and not soliciting their employees or customers to leave if I should leave. Thes two seem a bit rediculous though. Four years ago this company purchased the company that I originally was hired by. They say that their employees have in the past all had to sign a "similar" agreement. Can they require me to sign this if it was not a part of my initial employment?