Hindus/Gita and rituals
Sir, as you mentioned Gita/Vedas only offers solution to solve an individual problem. And not how to reach the highest position in any field.
People do varieties of pooja, rituals or yagya to fulfill their wish or to remove current bad phase in their life. Is this totally different from Gita/Vedas and does it provide solution like Gita.
Vedas contain two parts. The first part is called Karma Kanda. It contains varieties of pooja, rituals, yagya etc. One can engage a priest to perform these rituals FOR THE PURPOSE of material success. It could be for the purpose of getting a son, or building a house, or for earning lots of money, removal of obstacles in life and such things.
The second part of the Vedas is called Gnana Kanda or Upanishads. It contains the ultimate knowledge that is required for liberation.
The first part is for material success and the second part is for spiritual success (enlightenment). The first part can be done by engaging a priest while the second part need to be done by the concerned person personally. The first part contains the action to be done and the second part contains the knowledge to be learnt. The first part helps in Karma Yoga and Second part helps in Gnana Yoga.
Gits is largely a summary of the second part although it touches upon the first part by talking about Karma Yoga.
Thus when people use the first part of the Vedhas for the purposes mentioned by you. They need not understand what the mantras mean. But in the second part they need to understand.
Thanks for asking this important question. If you need more clarifications please do ask.