Does staying too long on a company worth it?

I've been with a company for almost eight years; I've also been with a company for only three months.  If a hiring manager looks at my resume, they always assume that I'm a job hopper. For me, again, "for me", on my own opinion, it's not worth it to stay for too long.  Looking back, my longest stay should have been  3 years only then I should have transferred to another company, and here are my reasons:

1.  There is a possibility that if I've stayed only for 3 years during my "early working years" and transferred immediately to another company, I could have earned the right amount of salary and my value is much higher right now.  I remember I was earning around 12k during my 5th year (yuck!) and I was being offered by another company at around 25k; I declined it because during that time I was "loyal" to my current company.  Some of my co-workers that have transferred to other companies are earning a higher salary and good benefits than me.

2. Growth - I've trusted too much the company that I've been working for during that time, thinking and believing them that my career will grow (I'm into I.T. industry); that they have plans for my career.  Unfortunately, I forgot that it is a business, money is the primary factor if you own a business - money first before anything else, that's the reality.  I just realized that you MUST have your own plans in terms of your career growth.  Don't believe too much that companies will help you grow in your career; you are the one that will decide on how you will grow, not them. Yes there are companies that will provide you training and certifications but are they really worth it?

3.   Salary/Income - this is one of the worst decisions that I've made; I've stayed with a company for too long even if I know that I have a low salary, that I should already be earning this or that amount.  I did not realized early in my career that one of the reasons that I'm working is for the salary, to EARN RIGHT and not just being happy on your job. Now I don't believe anymore in "just be happy with your job even if you are not earning the right amount of salary". What I do believe right now is "Money isn't everything, but it's part of everything" (I forgot who said this).

4. Now, when I'm reading job openings, the people with just 2-3 years of experience and me with almost 12 years of experience have the same value (oh my gosh!).  Companies will always look for the cheaper candidate, it's like "who cares if you have long experience? You want this job or not?"