The issue of the shirk of respect is very confusing for me. We have a tradition among our relatives that the younger person will bow slightly to his elders, at which point the elders will place their hands on the heads of the younger people as an expression of love, but the younger ones do not bow as the Muslim bows in his prayer.

Praise
be to Allah

It is not permissible to bow when meeting anyone, whether he
is a scholar or otherwise. 

Shaykh al-Islam Ibn Taymiyah said: 

With regard to bowing when greeting someone, it is not
allowed, as it was narrated in at-Tirmidhi that they asked the Prophet
(blessings and peace of Allah be upon him) about a man who bowed when he
meets his brother. He said: “No (do not do that).” That is also because it
is not permissible to bow or prostrate except to Allah, may He be glorified
and exalted, even though doing this by way of greeting was acceptable
according to the teachings of earlier Prophets, as in the story of Yoosuf,
“…and
they fell down before him prostrate. And he said: “O my father! This is the
interpretation of my dream aforetime…”
[Yoosuf 12:100]. But
according to our laws (sharee‘ah), it is not acceptable to prostrate except
to Allah. In fact there is even a prohibition on standing up in greeting for
one another as the non-Arabs do, so how about bowing and prostrating? That
which is a partial bow is also included in the prohibition.

End quote from Majmoo‘ al-Fataawa (1/377) 

And he said: 

With regard to lowering the head before elders such as
shaykhs and others, or kissing the ground in front of them, and the like,
these are things concerning which there is no dispute among the leading
scholars that they are prohibited. In fact merely inclining the back to
anyone other than Allah, may He be glorified and exalted, is prohibited. In
al-Musnad and elsewhere it is narrated that when Mu‘aadh ibn Jabal
(may Allah be pleased with him) returned from Syria, he prostrated to the
Prophet (blessings and peace of Allah be upon him and his family), and he
said: “What is this, O Mu‘aadh?” He said: O Messenger of Allah, I saw them
in Syria prostrating to their bishops and patriarchs, and they attributed
that to the teachings of their Prophets. He said: “They are lying, O Mu‘aadh.
If I were to instruct anyone to prostrate to anyone, I would have instructed
women to prostrate to their husbands, because of the rights that Allah has
given them over them. O Mu‘aadh, do you think that if you pass by my grave,
you would prostrate?” He said: No. He said: “Then do not do this” – or words
to that effect. 

Conclusion: 

Standing up, sitting, bowing and prostrating (which are
actions done in the prayer) are due only to the One Who is truly deserving
of worship, the Creator of the heavens and the earth. Whatever is due
exclusively for Allah cannot be directed to anyone or anything else in any
way, as in the case of swearing an oath by anything other than Allah, may He
be glorified and exalted. 

End quote from Majmoo‘ al-Fataawa (27/92-93) 

For more information on the issue of prostrating to anyone or
anything other than Allah, please see the answer to question no.
229780 

And Allah knows best.