I just copied that entire quote, but for the record I don't agree with the last part. I think a tax credit for savings (a reverse wealth tax) would be a terrible idea.
We saw that instead of spending your money irresponsibly, you decided to save for a rainy day. So we're gonna rain on your day
Now! =3
For the OP, the problem your conversation is having is that you're trying to pigeon hole an entire class of earners in to a very particular behavior, which would be difficult to prove to anyone. Let me propose the following example: the majority of high income earners save a mere (ex.) 10% of their income, which in money terms comes out to be far more than the average middle or low income earner will ever hope to save, or earn within the same amount of time. In such a frame, both of your statements come out correct from your own perspectives! Whether it's true or not will depend on the measured statistic, your category, and how the heck you would determine that data.. blah blah details.
At any rate, it's probably true that those with a large degree of spending money have a higher degree in freedom on what they choose to spend it on, including savings, investing, or luxuries. It is also reasonably accurate to say that as a person's income increases, their spending habits also has the
freedom to move up with it. With a higher income, they can also hoard more money, and even if it is a smaller percentage of their income, it can still be higher than what the average worker can produce. These are people, like you or I, and they make decisions on what they buy or don't buy just like everyone else does, and they make the decision to come up with a savings plan or not just like many other mid and low income earners out there.
The higher incomes simply gives them the freedom to do these things more easily due to differences in scale.