Chesedname, I notice that your question is about “everybody”. Let’s keep this about yourself and it would be alot easier to answer it. Before speaking about others, speak to them first.
We find that Moshe Rabbeinu asked Hashem the famous question of Tzaddik V’ra Lo. It is not clear if he got an answer. Moshe Rabbeinu was shown the plight of Rebbi Akiva and said, “Zu Torah V’zu S’chara?” On the other hand when we look at Rebbi Akiva himself, we find that he answers his Talmidim that this is the greatest opportunity in his life. No questions.
Back to the issue at hand, in the Gemmara in Shabbos we find that Rebbi asked Rebbi Yishmoel B’reb Yosi in what Zechus did the rich of Eretz Yisroel become rich. He answered that they give Maaser. Then he asked about the rich of Bavel, to which he replied that they are Mechabed the Torah.
First of all, from the fact that he was not satisfied with the first answer as pertaining to the Bavelites, shows us that the Mod is correct in that it is referring to real Maaser.
Second of all, nothing is a sure way to anywhere. Richness has to do with Mazel among other things. If you notice, the question is, how where the rich Zocheh. Not everyone will become rich, but in order to become rich there has to be a Zechus. If it helps, you can also think of it as adding gas to the engine. If it’s broken, leaking over-loaded or choked, the effect will be stopped or dampened. But, my point was more than that.
The concept that we learn from this Memra of Chazal also applies to Tzeddaka in general, of course. Now, of course it does not mean that you will surely get rich. It does mean that Hashem gives to those who give. The Maharal likens this to a well that as you take water from it, more flows in. If you speak to people about this you will hear remarkable stories of how after giving Tzeddaka they got helped from unexpected sources. I had my own experience a few days ago, when although very pressed, I gave somebody more than I would usually think of giving, and that day, I avoided a car accident at the last second.